Artificial Leaf Pumps Water and Makes Electricity

August 05, 2009

I can't get enough of this biomimetic stuff. I'm going to have to do a Wide Angle on it. There is so much technology out there inspired by nature. Take this artificial leaf, for example. A team of researchers (Ruba Borno, University of Michigan, Ann Arbor; Joseph Steinmeyer, MIT; and Michel Maharbiz, Univ. of California-Berkeley) looked at leaves in nature and saw that they work like pumps. Water in trees taken from the roots is pumped to the leaves and down the veins to the leaf's surface, where it meets the air and evaporates. It called transpiration.

These researchers fabricated an artificial leaf that does the same thing. It's made from a glass wafer that contains tiny veins. The end of the vein is open. As water evaporates at the end, it pulls other water out, moving the water at about 1.5 cm per second.

Generate Some Negawatts

July 15, 2009

While researching for the Wide Angle on the Smart Grid, I came across a term that I had never seen before: Negawatts. Nega what? Immediately I g=Googled and discovered that this term dates back to at least 1989, when experimental physicist and CEO of the Rocky Mountain Institute, Amory Lovins gave the keynote address (The Negawatt Revolution: Solving the CO2 Problem) at a Green Energy Conference in Montreal. I can't believe I never came across the word, but it's an important one to have as part of your volcabulary.

Nobel Prize Winner Says Wind is Not the Future

June 02, 2009

This week on Discovery Tech, we're talking about wind power and it's potential to supplant fossil fuels. I've read over and over -- and also have spoken with experts who say -- that there's so much wind out there, we could power the United States five times over. But one of the biggest challenge is storage. Right now, when you generate wind energy, you have to use it or lose it. Or you have to store it, perhaps in batteries. But that technology isn't available yet. Sure, we have batteries, but not ones that can store megawatts of energy being generated on wind farms.

That's part of the reason that 1968 Nobel Prize winner in physics Jack Steinberger said the United States (i.e. Obama) shouldn't be focusing so much on wind power. They should be focusing on solar thermal power, Steinberger said. You may immediately think about solar panels, that is photovoltaics, that convert solar energy directly into electricity. But that's not what Steinberger was talking about. He was talking about solar collectors that concentrate the sun's energy to heat water to very high temps. That hot water is turned into steam, which is used to turn a turbine and produce electricity. Spain just built a huge facility to do this -- the PS10 Solar Tower (image).

Recently, Greenpeace released a report saying that solar-thermal power farms could provide 25 percent of the world's electricity needs by 2050.

Personally, I think we need both solutions, since the sun is not shining consistently in all places and there are plenty of people against the idea of blanketing sunny locations with solar collectors.